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Compartmental analysis of the disappearance curve of serum cholesterol specific activity after an intravenous administration of a tracer does of cholesterol-4-14C was carried out in five patients with resection of the distal small intestine, cecum, and proximal colon. The data fit best a two compartment model in all five cases with the rapidly exchangeable pool of 16.6+/-3.2 g (mean +/- SD, 60% of the mean of 15 normal subjects) and the slowly exchangeable pool of 31.5 +/- 10.9 g (65%). The reduction of the pool sizes was associated with a shorter mean transit time of cholesterol, 22.15 +/- 8.07 days (40%) and increased turnover rate, 2.42 +/- 0.72g/ day (172%). Direct fecal analysis for the neutral sterols and bile acids derived from the exchangeable pool confirmed the turnover rate obtained from the compartmental analysis. The increased fecal excretion was mainly in the bile acid fraction. The study suggests that the ileal and proximal colon resection results in bile acid malabsorption which, in turn, increases hepatic cholesterol and bile acid synthesis. The synthetic rates, however, could not compensate totally for the excretory rate. Therefore, the pool size decreased to a new low steady state of equilibrium.  相似文献   
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We recently showed that in vitro heterophil functional efficiency in commercial broiler chickens is genetically controlled and may be a sex-associated trait. To further characterize the genetic mechanism(s) of heterophil functional efficiency, we wanted to determine whether the feathering gene, present on the Z sex chromosome, contributes to heterophil functional efficiency. Heterophils from two pairs of broiler lines were evaluated; each pair contained a fast feather (FF) (lines A and X) and a slow feather (SF) line (lines B and Y). On days 1 and 4 post-hatch, heterophils isolated from two sets of pure line broilers (A and B, and X and Y) were evaluated for their ability to (1) phagocytize Salmonella enteritidis, and (2) exhibit bactericidal activity against S. enteritidis. On days 1 and 4 post-hatch, heterophils isolated from the FF lines were statistically (P < or = 0.02) more proficient at phagocytizing S. enteritidis than heterophils from SF lines. Bactericidal activity was also statistically (p < or = 0.02) greater on day 1 post-hatch in the heterophils isolated from FF lines compared to heterophils isolated from SF lines. These data indicate that the presence of the FF gene locus on the Z sex chromosome contributes to heterophil function and may contribute to the early innate immune competence of a flock.  相似文献   
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Fluoride concentration in whole saliva and in separate gland secretions was studied after a 7-day fluoridated milk regimen (1mg F per day) in 12 healthy schoolchildren aged 10-13 years. A 2-week fluoride-free run-in period preceded the tests in order to establish the endogenous baseline levels. Unstimulated and stimulated whole saliva and stimulated parotid and submandibular-sublingual saliva were collected at 1, 3, 6, 12 and 24h after F-milk ingestion, and fluoride concentrations were determined with an ion-selective electrode. Typical time-dependent excretion curves were obtained in all collected secretions. The fluoride levels were significantly elevated 1 and 3h in whole saliva and up to 6h in the gland secretions after intake of fluoridated milk when compared to baseline values. When acid-stimulated, the submandibular-sublingual glands were the major contributors of fluoride in the oral cavity. In conclusion, the results of this study demonstrate that fluoride ingested with milk is excreted through the salivary glands, indicating that the bioavailability of fluoride from milk equals that of other vehicles.  相似文献   
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Transforming growth factor beta (TGF-beta) is a potent inhibitor of proliferation in most cells and exerts its effects through an interaction with membrane receptors type I (TGF-betaRI) and type II (TGF-betaRII). Recently, we have demonstrated a correlation between the loss of expression of TGF-betaRI and TGF-betaRII and increasing Gleason score in archival human prostate cancer tissues. To evaluate the potential prognostic value of this observation, the present study investigated the expression of TGF-beta receptors in association with disease progression after the initial diagnosis in 52 archival human prostate cancer tissues. The expression of both TGF-betaRI and TGF-betaRII was correlated with the Gleason score, clinical tumor stage, 4-year survival rate, and serological recurrence rate after radical prostatectomy. Results revealed that there was a significant association between the Gleason score and the loss of expression of TGF-betaRI (P < 0.025) and TGF-betaRII (P < 0.01). However, only the loss of TGF-betaRI expression showed a statistically significant association with the clinical tumor stage (P < 0.05), 4-year survival rate (P < 0.05), and serological recurrence rate after radical prostatectomy (P < 0.025). Therefore, these data indicate that the loss of TGF-betaRI expression as measured by immunohistochemical staining may be a potential prognostic marker in prostate cancer patients.  相似文献   
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The course of changes in the activities of enzymes degrading juvenile hormone (JH), epoxyde hydrolase (JHEH) and JH-esterase (JHE) was studied in two lines of Drosophila virilis (101 and 147) and in two lines of D. melanogaster (Canton-S and 921283). It was established for D. virilis that changes in the JH titre during pupal-adult development is determined by the activity level of JHE rather then JHEH, while in D. melanogaster developmental changes in JH titre are related to changes in the activity level of both JHE and JHEH. In adults of D. virilis, the high level of JH-hydrolysing activity is determined by JHE and in those of D. melanogaster by JHEH. Differences in the course of changes in the JHE activity level between adults of lines 101 and 147 of D. virilis were found, and also in the JHEH activity level between adults of lines Canton S and 921283 of D. melanogaster. It was shown that attainment of a definite JHE activity level in females of lines 101 and 147 agrees well with the onset of oviposition of fertilized eggs. The possible role of JHE in reproduction of D. virilis is discussed.  相似文献   
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